The present invention relates to improvements concerning a bubble humidifier used to humidify oxygen prior to dispensing the oxygen to a patient for medical purposes.
Oxygen is supplied to patients for a variety of medical reasons. The conventional techniques for generating oxygen typically remove essentially all of the moisture from the generated oxygen so that the oxygen essentially has zero percent relative humidity. Prior to supplying the generated oxygen to a patient, the oxygen is generally sent through a bubble humidifier, or some other humidifying apparatus, where a suitable amount of humidity is added to the oxygen prior to supplying the same to the patient for a medical application.
Standard humidifiers typically operate well for humidifying oxygen at an oxygen flow rate of from about 2 to 4 liters per minute. However, when the flow rate of the supplied oxygen is increased to 6 liters per minute or greater, the currently available bubble humidifiers do not work satisfactorily. In particular, the currently available bubble humidifiers have a tendency to jiggle and shake excessively due to the increase in the oxygen flow rate through the bubble humidifier. Such jiggling or shaking of the bubble humidifier, in turn, has a tendency to cause a valve component of the pressure relief device for the bubble humidifier to become unseated and vent a portion of the moisturized oxygen from the bubble humidifier to the surrounding environment rather than the supplying the same to the patient. Such venting of the supplied oxygen, via the pressure relief device, also causes the pressure relief device to emit a xe2x80x9cwhistlingxe2x80x9d sound. This sound generally indicates that at least a portion of the supplied moisturized oxygen is not being conveyed to the patient, e.g., the moisturized oxygen supply conduit for supplying the oxygen to the patient may have a kink therein or is somehow clogged or occluded. In response to the xe2x80x9cwhistlingxe2x80x9d sound, the medical personnel will then undertake corrective action, e.g., remove the kink or occlusion from the moisturized oxygen supply conduit.
The conventional pressure relief devices work reasonably well for low oxygen flow rates, e.g., flow rates of 4 liters per minute or less. However, when the flow rate of the oxygen is increased to 6 liters per minute or greater, the conventional pressure relief devices have a tendency to malfunction as the valve of the pressure relief device does not always properly reseat itself to ensure that all of the supplied moisturized oxygen is again conveyed to the patient, via the moisturized oxygen supply conduit, rather than being vented to the surrounding environment
The increased oxygen flow rate also has a tendency to cause the oxygen bubbles to coalesce and when the coalescing bubbles filter up through the liquid contained in the bubble humidifier and break the liquid surface. Upon breaking the liquid surface, liquid is splashed and sprayed toward the outlet of the bubble humidifier and into the moisturized oxygen supply conduit. This splashed and sprayed liquid, e.g., water, is then conveyed along with the moisturized oxygen toward a cannula, connected at a remote end of the moisturized oxygen supply conduit, which supplies the moisturized oxygen into the nostrils of a patient. A water trap is installed, along the moisturized oxygen supply conduit, to remove small quantities of liquid from the moisturized oxygen. The conventional water traps work adequately for removing small amounts of water from the moisturized oxygen supply conduit, but the water trap can become quickly clogged if a large quantity of liquid enters the moisturized oxygen supply conduit and is conveyed toward the patient.
Wherefore, it is an object of the present invention to overcome the above mentioned shortcomings and drawbacks associated with the prior art bubble humidifiers.
Another object of the present invention is to provide a bubble humidifier which is able to add a sufficient amount of moisture to oxygen for a medical application, while minimizing the amount of liquid, e.g., water, which enters into the moisturized oxygen supply conduit exiting from the bubble humidifier.
A further object of the present invention is to provide a pressure relief device which reliably indicates when there is a blockage, kink or some occlusion in the moisturized oxygen supply conduit and also facilitates proper reseating of the valve element once the blockage, kink or occlusion is eliminated from the moisturized oxygen supply conduit.
Yet another object of the present invention is to minimize the amount of liquid that enters into the moisturized oxygen supply conduit and must be removed by a water trap to minimize the associated maintenance required for use of the bubble humidifier.
A still further object of the present invention is to provide a larger bubble humidifier surface area for the bubbles emitted by the diffuser to facilitate a greater and improved dispersion of the oxygen bubbles emitted by the.
Yet another object of the present invention is to minimize the coalescence of the bubbles as they contact the side wall of the container so as to minimize the amount of turbulence of at the surface of the liquid as the oxygen bubbles migrate up through the liquid contained in the bubble humidifier during operation.
The present invention also relates to a bubble humidifier for adding humidity to supplied oxygen, the bubble humidifier comprising: a humidifier base for containing a quantity of liquid; a cover for the humidifier base; the bubble humidifier having an oxygen inlet for supplying oxygen to the bubble humidifier and a moisturized oxygen outlet for connection to a moisturized oxygen supply conduit for supplying humidified oxygen to a patient, and the oxygen inlet being connected to a diffuser for diffusing the supplying oxygen within the bubble humidifier; the bubble humidifier having a pressure relieve device for relieving excess pressure generated within the bubble humidifier during operation thereof; and the bubble humidifier defining a longitudinal axis; wherein the diffuser is arranged to discharge the oxygen from the diffuser substantially at an angle normal to the longitudinal axis of the bubble humidifier to minimize flow of liquid, contained within the humidifier base, from entering the moisturized oxygen outlet and being conveyed along the moisturized oxygen supply conduit during operation of the bubble humidifier.
The present invention also relates to a method of adding humidity to supplied oxygen via the bubble humidifier, the method comprising the steps: providing a humidifier base containing a quantity of liquid; covering the humidifier base with a cover; providing the bubble humidifier with an oxygen inlet for supplying oxygen to the bubble humidifier, connecting an moisturized oxygen outlet to a moisturized oxygen supply conduit for supplying humidified oxygen to a patient, and connecting the oxygen inlet to a diffuser for diffusing the supplying oxygen within the liquid contained by the humidifier base; providing the bubble humidifier with a pressure relieve device for relieving excess pressure generated within the bubble humidifier during operation thereof; defining a longitudinal axis with the bubble humidifier; discharging, via a diffuser, the oxygen from the diffuser substantially at an angle normal to the longitudinal axis of the bubble humidifier to minimize flow of liquid, contained within the humidifier base, from entering the moisturized oxygen outlet and being conveyed along the moisturized oxygen supply conduit during operation of the bubble humidifier.